rust-lang/rust — pull request #15256 by erickt (2014-06-29 19:34:53+00:00)
Title: Optimize {result,option}::collect

The bug #11084 causes `option::collect` and `result::collect` about twice as slower as it should because llvm is having some trouble optimizing away the scan closure. This gets rid of it so now those functions perform equivalent to a hand written version.

This also adds an impl of `Default` for `Rc` along the way.